1. Field of Invention
This invention is directed generally to bearing assemblies, and more particularly to an inner ring of a concentric bearing where the inner ring has compressible finger extensions for use with a shaft locking collar.
2. Background of the Invention
Bearing assemblies are installed in a broad variety of industrial applications and settings. It is known in the art to use a set screw, or series of set screws, to securely attach the inner ring of the bearing to a rotating shaft. One such bearing is the Goldline Set Screw bearing available from SealMaster(copyright). In addition, it also known in the art to use a concentric inner ring having spaced, compressible finger extensions, such that a locking collar can be used to clamp the inner ring to the rotating shaft. One such bearing is the Goldline Skwezloc(copyright) bearing also available from SealMaster(copyright) that utilizes a locking collar. Various alternative locking collars are disclosed in U.S. Pat. No. 5,863,137.
Many bearing applications are required in corrosive environments or in harsh operating condition. For example, in food handling applications, stainless steel shafts are often used to protect against the corrosive, acidic effects of various food products, such meat, poultry, and beverage applications, where no rust and easy cleaning is desirable. Several undesirable effects may arise when using the above described set screw bearings. The set screws, when tightened against the relatively soft stainless steel shaft, can damage the shaft, requiring costly replacement and costly downtime. Normally, to alleviate the undesirable effects of using a set screw, a bearing having compressible finger extensions and a locking collar can be used to more evenly distribute the clamping force about the shaft. However, those in food handling applications are reluctant to use bearings with the compressible finger extensions, because the slots between the extensions provide a place for bacteria and other contaminants to reside. In food handling applications, the presence of any bacteria or contaminants is highly undesirable, as they could contaminant the food that is being processed.
Accordingly, there is a need to provide a bearing assembly suitable for use in food handling applications, and other applications where the presence of bacteria or contaminants is undesirable, that does not present the drawbacks associated with the use of a set screw and that also does not have the slots, or crevices associated with prior art bearings having compressible finger extensions where bacteria and other contaminants may reside.
The present invention is specifically directed to the inner ring of a concentric bearing locking device where the inner ring has compressible finger extensions such that the inner ring is suitable for attachment to a rotating shaft via a locking collar. The present invention is further provided with finger extension slot seals that fill the slots, or area between the finger extensions, to help eliminate the areas where bacteria and contaminants may congregate. A finger extension seal may further cover the outer circumference of the extensions to allow a further seal between the extensions and the locking collar. In a preferred embodiment, the finger extension seal is affixed to the finger extensions by using a low pressure overmolding operation which can be performed using a hand mold. Santoprene, or any other suitable elastomeric polymer, may be used as the seal material. Santoprene is desirable as it has previously received FDA approval for use in the food industry. Nonetheless, any number of types of seal material may be used. It is desirable that the seal material does not cover the inner diameter of the inner ring during the molding operation. To prevent the seal material from covering the inner diameter, a machined collar or expandable bladder may be used during the overmolding operation.